This invention relates to a medicant injection device of the hypodermic needle type. More particularly, it relates to such a device that is especially suited to self-administration of the medicant. There is a strong demand for such devices and the ones available are not without shortcomings.
They are commonly used by persons with severe allergies. For instance, some persons are allergic to specific foods such as peanut butter, egg whites, walnuts and can become suddenly and seriously ill if they get a small amount of the substance they are allergic to in their food. They become overtaken with a life-threatening swelling of tissue that can in most cases be treated, at least on an emergency basis, with an injection of adrenalin or other anti-histamine. An on-the-spot injection of the appropriate medicant will give them enough time to seek the nearest professional and some persons seriously affected this way carry appropriate medication for hypodermic injection. The medicant injection device of this invention is suitable for this use.
Obvious requirements for a mediant injection device of this service are that it be easy to use because these users are not professional medical people and that it be as inexpensive as possible because these devices are used once and then thrown away.
The injection device most commonly used by allergy suffers is the plunger-cylinder dispenser in various forms, for delivering medicant through a hypodermic needle. However, these devices have proven neither easy to use nor inexpensive. Quite often, the user is not a medical person, and/or is in an excited state of mind. In these cases, the elongated plunger cylinder configuration is cumbersome to hold, difficult to align for injection and difficult to maintain steady in use because of the elongated nature of the device and the smallness of its surface that interfaces with the body. Plunger cylinder needles are also relatively expensive to manufacture.
Reliance on the plunger cylinder type of medicant dispenser in various forms of complexity with its attendant difficulties of use and cost in the single-use/throw-away medicant dispenser has been of long standing.
It is therefore an object of this invention to provide an easy-to-use, inexpensive single user throw-away hypodermic needle medicant injector that overcomes the forgoing problems of the prior art.
This and other useful objects are achieved through the ingenious use of a fluid-operated medicant injection device, that will seat with stability on the body and that has a diaphragm to both carry the needle forward and compress the medicant chamber to discharge the medicant through the needle into the body.